7Z に ZIP コンバーター — 高速＆無料

The 7-Zip Archive format uses the LZMA2 algorithm to achieve compression ratios 30-70% better than ZIP, with optional AES-256 encryption. Converting to ZIP produces an archive file that bundles multiple files using DEFLATE or Store compression with a central directory index, supported natively on every major operating system. This conversion changes the file's encoding, compression method, and supported feature set. The contained files are extracted and re-packed with the target format's compression; the files themselves stay bit-for-bit identical — only the container and ratio change. This makes ZIP the practical choice when the destination system requires it or when the target format offers better compatibility or compression. 1converter runs this conversion on the server: your file is uploaded encrypted over HTTPS, converted using trusted open-source libraries, and the output is held for 24 hours before automatic deletion.